Re: how to find sin 5 degrees

Re: how to find sin 5 degrees

Thank you for the help! Actually, I too did the same and got an equation of 3rd power with complex roots :-)But the problem is, I need this for my daughter who is in class 8 and they haven't learned complex numbers as yet....I think that the teacher made a mistake in the question paper - she wrote 5 instead of 15 :-)

Re: how to find sin 5 degrees

Hi;

Relatively Quantum has a point. Since some calculators (Texas Instruments- I think, I remember reading about it and HP) have abandoned Economized Taylor series and even Pade approximants in favor of that old Cordic algorithm which uses rotations to calculate. But it does need a table lookup initially so it violates one of his restrictions.

Last edited by bobbym (2009-10-19 16:53:51)

In mathematics, you don't understand things. You just get used to them.If it ain't broke, fix it until it is.No great discovery was ever made without a bold guess.

Re: how to find sin 5 degrees

Hi vishalbhai;

While looking for something else I found this page and remembered your post.

This guy is doing what we thought was impossible, Turned out Ptolemy and Archimedes solved this problem satisfactorily, without calculators or Taylor series, Pade approximants or Cordic. Just from knowing a few trig relations and some values of common angles. You should be able to get as close to sin(5°) as you wish,

Re: how to find sin 5 degrees

Draw a right angled triangle with :theta = 5, and find the ratio of the Perpendicular and Hypotenuse

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.''God exists because Mathematics is consistent, and the devil exists because we cannot prove it'I'm not crazy, my mother had me tested.

Re: how to find sin 5 degrees

Of Course , But what should be the real solution?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.''God exists because Mathematics is consistent, and the devil exists because we cannot prove it'I'm not crazy, my mother had me tested.